textproduct: Quad Cities

KEY MESSAGES

- The break in the heat will last through Monday night, followed by hot weather Tuesday and Wednesday, with highs reaching the 90s, but with substantially lower humidity values than recent weather.

- Showers and storms, some of which may be severe, are likely (60- 90%) Tuesday afternoon through the overnight hours. SPC has issued a Marginal, level 1 of 5, risk for severe storms along and north of an Ottumwa to Muscatine to Galena line.

SHORT TERM /THROUGH MONDAY/

Issued at 239 AM CDT Sun Sep 6 2026

Temperatures this morning have dropped into the upper 60s to low 70s, with dew points not far behind. As an area of mid to high clouds moves southward, a low stratus deck has been expanding westward. With small dewpoint depressions and light winds, any radiational cooling that occurs before this low stratus moves in could be supportive of areas of patchy fog. This fog is most likely along and north of a line from Vinton to Moline, lasting up to 1-2 hours after daybreak.

The remainder of today will be pleasant and noticeably cooler compared to yesterday's temperatures and heat indices. While highs are still quite warm in the 80s, a drier airmass with dewpoints in the upper 60s will keep heat indices below 95 degrees. Monday will be similar if not a degree or two cooler as the ridge continues to sit just to our south over the central CONUS.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/

Issued at 239 AM CDT Sun Sep 6 2026

After a brief reprieve, an active and warm stretch of weather is in store for Tuesday and Wednesday as the midlevel ridge leans eastward. Moisture will begin to feed back into the area, as seen by an IVT tongue of 400-700 kg m-1 s-1 from the Gulf into an amplifying trough across Saskatchewan and Manitoba. For the first half of the day Tuesday, this will lead to increased heat across the southwestern half of the CWA. Fortunately, this heat will feel less oppressive than the recent heatwave due to dewpoints in the mid 60s, which will keep any chances of 100 degree heat indices localized to parts of far southeast low and northeast Missouri. That being said, it will still be hot with heat indices of 95 degrees or more possible (30-70%) Tuesday afternoon along and south of a Cedar Rapids to Aledo line. Wednesday will also be warm, though there is uncertainty in high temperatures due to the potential for storms Tuesday afternoon and evening into the overnight hours.

In addition to the potential for seasonally hot temperatures, storm chances will return Tuesday afternoon into Wednesday. As mentioned previously, an amplifying shortwave and surface cyclone will move across south-central Canada. Forcing along a cold front will support the potential for showers and storms into the overnight hours. While there will be sufficient shear and instability to support severe potential, the question of timing and capping potential introduce some uncertainty. At this time, SPC has introduced a Marginal, level 1 of 5, risk of severe storms along and north of an Ottumwa to Muscatine to Galena line.

Past Wednesday, flow aloft transitions to more zonal, returning us to more seasonable temperatures for yet another brief reprieve. However, increasing heat and humidity appear possible towards the end of the week, continuing above normal temperatures through mid- September.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 101 AM CDT Sun Sep 6 2026

VFR to MVFR and potentially IFR conditions are possible during the first half of the TAF period. Currently, a deck of mid to high clouds is moving southward through the area, with a secondary deck of low stratus developing westward from Lake Michigan with SCT to BKN MVFR CIGs of 1500-2000 ft. After these CIGs move into the DBQ/MLI/CID terminals early this morning, areas of fog with VFR to MVFR VSBYs are expected from 06/10-14Z. Chances for IFR or lower VSBYs (20-40%) are highest at DBQ, hence the inclusion of an IFR TEMPO group, but low confidence in IFR VSBYS have excluded it from MLI/CID at this issuance. Past 06/17Z, VFR conditions are expected at all terminals through the remainder of the period.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.